A foundational principle of McVay's newly evolved offense is that WRs MUST BLOCK.
Tutu can't. He's just too darn small, and if tries he'll get run over like road kill.
Plus, he may be fast in a straight line, but clearly he is not elusive. And, he MUST have a bunch of separation to make a play on the ball.
With his attributes he can only be used in a limited set of plays. AND....the biggest negative....he can't play on STs.
Anyone that is going to be the 4th or even 5th WR MUST contribute on STs. Otherwise, he's a waste of a precious roster spot.